Panasonic Toughbook CF-18BHKZXDM Service Manual page 85

Main 31 2.5V 1.25V DC/DC
VB25/VC125
1
2
010:F3;018:F4;035:A3;035:B9;035:D3
3
4
Vout=0.8*(1+RH/Rl)
5
6
7
8
9
4;022:F3;023:H5;024:D8;035:A5;035:B11;035:D5
10
11
A B
DCIN&BATT
3
2SK3019TL
2
Q49
R354
3 1
NU
SLP_S4#
2 UNR9213J0L
Q48
1
R350
4700pF
NU
B
1608
C445
R353
0
R348
0 R351
470p
NU R352
100p
22K
C446
C450
R349
Vref=0.792 0.808V
4.7K
RH=9.9 10.1Kohm
1%
RL=4.653 4.747Kohm
Vout=Vref*(1+RH/RL)
Vout=2.4437 2.5619V
(SPEC Vout=2.375 2.625V)
SGND
C449 100p
2200pF
5.1K
B
1608
R355
C448
DCIN&BATT
R356
1M
R357
3
C447
220p
2SK3019TL
2
Q18
1
3
SLP_S3# UNR9213J0L
2
Q13
SGND
1
C D
R359
1M
R360
10
1608 50V
C463
0.01u
C464
0.1u
1 RUN/SS 16
BOOST
2 PGOOD TG 15
3 VRNG 14
SW
2125
4 FCB PGND 13
C465
0.22u
5 ITH 12
BG
6 SGND 11
INTVCC
7 ION 10
VIN D21
8 VFB 9
EXTVCC
C462
6.3V
NU
C466
NU VB5 10u
2125
C451
R358
10K
1%
PGND
VB25
1 SVIN PVIN 16
L26
A915AY-1R1M=P3
2 PGOOD 15 1 2
SW
3 ITH SW 14
4 VFB 13
PGND
330K
5 RT PGND 12
6 VREF 11
SW
7 RUN/SS 10
SW
8 SGND 9
PVIN
PGND
E F
DCIN&BATT
25V
3225
C468
B
10u
PGND
Q50
FDS6690A VB25=2.5V
1 S 8
D
2 S 7
D
3 S 6
D
4 G D 5
Nch-MOSFET L27
SOP8 Fairchild
1 2
Q51
919AS-4R7M=P3
FDS6690A
1 S 8
D
2 S 7
D
3 S 6
D
4 G 5
D
Nch-MOSFET
6.3V
SOP8 Fairchild
+
D22 C469
D
10u
2125
EC10QS04-TE12L
PGND
VC125=1.25V 62.5mV@1.5A
VC125
VB25 MEMREF
R361
EEFUD0D181R 1% R548
10K
10
SP-CAP
+ 2V
3
+
C467
1
180u
O
2 NJM12904V(TE1)
-
R362 IC53
1%
10K
VB25
SGND
R188
MEMREF_DIMM
1%
10K
R549
PGND
10
5
+
7
O
R189
6 NJM12904V(TE1)
-
1%
IC53
10K
SGND
G H I
125mV@6A
VB25
SPCAP SPCAP
4V + 4V
EEFUD0G151R
EEFUD0G151R
C470 C471
D
NU 150uF
VB5
8
V+
C3 V-
0.1u 4 IC53
NJM12904V(TE1)
SGND
J